Which players caught the eye?published at 09:23 British Summer Time
First impressions of new Champions League format
Emlyn Begley
BBC Sport
Harry Kane scored four goals for Bayern Munich as they smashed Dinamo Zagreb 9-2. That already takes him halfway to last season's Golden Boot total.
Three other players scored two goals, all for German clubs - Borussia Dortmund's England Under-21 winger Jamie Gittens, Bayern's Michael Olise and Bayer Leverkusen's Florian Wirtz.
The goalkeeper with the most memorable impact in the first round of games was Arsenal's David Raya, who performed a stunning double save - including a penalty stop - to deny Atalanta striker Mateo Retegui.